Yes and yes. (And I'm going to call [MENTION=21169]Doug McCrae[/MENTION] to join in any Monster Mark discussions.)Anyone remember the Monster Mark (I think first published in White Dwarf)?
The Monster Mark has two problems though, in my view. First, it rates all monsters against a first level fighter, which means that I think it exaggerates the real ingame power of higher HD monsters.
Illustration:
[sblock]Take the following two characters:
1st level fighter with AC 2, 1d8 hp and doing 1d8 damage and hitting AC 2 on 18+;
3rd level fighter with AC 2, 3d8 hp and doing 1d8+1 damage (magic sword) and hitting AC 2 on 15+ (magic sword again).
The 1st level fighter requires, on average, 1 hit to kill itself. This takes it 20/3 rounds to achieve, in which time it takes, on average, the same amount of damage, for a MM of 4.5.
The 1st level fighter requires, on average, 3 hits to kill the 3rd level fighter, which takes on average 20 rounds. In which time the 3rd level fighter deals 20 * 6/20 * 11/2 = 33 hits of damage, for a MM of 33.
Thus, rated against a 1st level fighter, the 3rd level fighter is nearly 8 times tougher.
But now let's rate both against the 3rd level fighter.
The 3rd level fighter requires, on average, 9/11 of a hit to kill the 1st level figher. This takes it 9/11 * 20/6 = 30/11 rounds to achieve. In that time it suffers 30/11 * 3/20 * 9/2 = 81/44 hits, for a MM of a bit less than 2.
The 3rd level fighter requires, on average, 27/11 hits to kill itself. This takes it 27/11 * 20/6 = 90/11 rounds. In this time, of cousre, it takes the same amount of damage it has inflicted, or 27/2 hits, for a MMM of 13.5.
Thus, rated against a 3rd level fighter, the 3rd level fighter is less than 7 times tougher than the 1st level fighter.[/sblock]
The second problem is that the multipliers to MMs for special abilities are somewhat arbitrary, and especially when many special abilities are involved are very difficult to judge and compare. It is a bit like the Bodak issue from 3E - what CR is it, given that it is physically little thread but has a death gaze attack that even high level PCs might fail against?
Still, it was more systematic than the official systems in B/X and AD&D, and I used it back in the day!